I think you will find John's link helpful. Especlially the part about changing the channel on your router. That made a world of difference for me. I use to always switch back and forth. After changing the channel I have had solid UMA. I know in your T-Mobile email they said channel 11 but try more than just 11.

agreed, actually, stay away from 1, 6, and 11... those are default channels for a lot of brands of routers.

i'd personally try 3, 7, or 9. also download "network stumbler" and scan your area for all networks to see what their settings are so you can pick a clear channel.

there are also quite a few other router settings to help optimize the connection. we can go into these later once you get home and test your phone since you've done the hard reset.

lastly, the suggestion to do a battery pull is probably your best bet before fuggling around with any other settings.